Abstract In spite of their widely-spread use across the globe, the domestic solar water heaters are still subject to essential, technical difficulties that need to be deeply studied. Such technical impediments are latent in how appropriate to each other the different, mutually-dependent components of the system are; and how appropriate they are to the prevailing meteorological conditions of the application site which is still under research and development. This thesis presents a clear-cut, straightforward mathematical model that determines the basic factors influencing such systems, and, in specific, discusses the optimum design month as well as the optimum tilt angle of the solar collector, bearing in mind the contribution of the energy obtained to meet the targeted load. Furthermore, the study considers the required thermal capacity that should be provided by the solar collector. To avoid assumptions that could be unjustified in practice, and to get as precise results as possible, the study was thoroughly based on normalized mathematical parameters. In the case where the total demand for energy used in water heating is to be fully satisfied by the solar energy system, provided that the required temperature of the heated water is 45oC and consumption is 100 (litre/day) per person for a given house, the results of the study concluded that according to the climate information of Tripoli city, 32.68°N latitude, the optimum design month is December, the optimum tilt angle is 75°, and the solar collector area fulfilling the following specifications: Glazed type, Fr () = 0.58, and Fr UL= 4.00 (W/m2oC) is 2.83 square meters. On the other hand, the results suggest an optimum tilt angle of 50°, which is the same angle obtained by the traditional technique, and solar collector area of 1.6 square meters if up to 80% of demand is to be covered by solar energy.
علاء بلقاسم العلوني (2010)

Most of organizations (both national and international) have struggled with many difficulties during the past decades due to many problems, creating a negative impact on the productivity and utilization levels of many institutions around the globe, and within Libya in particular. This paper presents the current role, relevance, trends and challenges with respect of quality management applications in educational field within Libya as a case study. It outlines an overview of the current state of art to show how in the face of growing global competitiveness quality at the levels of knower, knowing and known elements of educational system using unified field of all the laws of nature, are deriving the benefits of the quality techniques. The paper also investigates the current implementation levels of Total Quality Management (TQM) as a philosophy for improving the quality levels within some academic and training institutions within Libya. A survey methodology has been applied in this research where some findings from interesting case studies are presented to show the benefits of successful TQM implementations originally developed for manufacturing industry. The paper has also pointed to areas where senior managers within the surveyed organizations should take immediate actions to achieve effective and successful TQM implementations, thereby improving their position in this competitive marketplace. arabic 17 English 115
Rajab Abdallah Abdulqader Hokoma(1-2015)

Making decisions is considered as the key role in achieving the desired goals within any organization. Moreover, making decisions in oil & gas industry is becoming a key factor for improving the work performance throughout practicing the most effective tools and techniques. The main purpose of this paper is to identify how individuals making their decisions within operating oil and gas companies. The required data for this paper were acquired by conducting several interviews with decision makers, and a questionnaire survey was also developed, besides reviewing the related literatures. Decision making processes in Libyan oil & gas operating companies were being investigated. The main findings show that over half of participants always consider safety, security and uncertainty issues when making their decisions, meaning that, it is a good indication of taking precautions when making decisions. Additionally, the majority of participants always double check their information resources, which is also a good indication of increasing the quality decisions and enhancing the work performance. Based on the findings, a number of recommendations were proposed for improving the processes of making proper and effective decisions within this business area arabic 13 English 77
Rajab HOKOMA, Hanan Zawam Aburas(1-2019)